pdgLive

${{\mathit B}^{0}}$ MEAN LIFE

INSPIRE JSON PDGID:

The ${{\mathit B}^{0}}$ mean life is defined and computed as 1/${\Gamma}_{{\mathit B}^{0}}$, where ${\Gamma}_{{\mathit B}^{0}}$ is the average decay width of the ${{\mathit B}^{0}}$ mass eigenstates.

VALUE ($ 10^{-12} $ s)

DOCUMENT ID

TECN

COMMENT

$\bf{ (1511.3 \pm2.7) \times 10^{-3}}$

OUR EVALUATION $~~$(Produced by HFLAV)

$1.5053$ $\pm0.0012$ $\pm0.0035$

ATLS

${{\mathit p}}{{\mathit p}}$ at 13 TeV

$1.499$ $\pm0.013$ $\pm0.008$

BELL

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

$1.511$ $\pm0.005$ $\pm0.006$

CMS

${{\mathit p}}{{\mathit p}}$ at 8 TeV

$1.527$ $\pm0.009$ $\pm0.009$

CMS

${{\mathit p}}{{\mathit p}}$ at 8 TeV

$1.534$ $\pm0.019$ $\pm0.021$

D0

${{\mathit p}}{{\overline{\mathit p}}}$ at 1.96 TeV

$1.499$ $\pm0.013$ $\pm0.005$

LHCB

${{\mathit p}}{{\mathit p}}$ at 7 TeV

$1.524$ $\pm0.006$ $\pm0.004$

LHCB

${{\mathit p}}{{\mathit p}}$ at 7 TeV

$1.524$ $\pm0.011$ $\pm0.004$

LHCB

${{\mathit p}}{{\mathit p}}$ at 7 TeV

$1.509$ $\pm0.012$ $\pm0.018$

ATLS

${{\mathit p}}{{\mathit p}}$ at 7 TeV

$1.508$ $\pm0.025$ $\pm0.043$

D0

${{\mathit p}}{{\overline{\mathit p}}}$ at 1.96 TeV

$1.414$ $\pm0.018$ $\pm0.034$

D0

${{\mathit p}}{{\overline{\mathit p}}}$ at 1.96 TeV

$1.504$ $\pm0.013$ ${}^{+0.018}_{-0.013}$

BABR

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

$1.534$ $\pm0.008$ $\pm0.010$

BELL

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

$1.523$ ${}^{+0.024}_{-0.023}$ $\pm0.022$

BABR

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

$1.533$ $\pm0.034$ $\pm0.038$

BABR

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

$1.497$ $\pm0.073$ $\pm0.032$

CDF

${{\mathit p}}{{\overline{\mathit p}}}$ at 1.8 TeV

$1.529$ $\pm0.012$ $\pm0.029$

BABR

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

$1.546$ $\pm0.032$ $\pm0.022$

BABR

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

$1.541$ $\pm0.028$ $\pm0.023$

OPAL

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.518$ $\pm0.053$ $\pm0.034$

ALEP

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.474$ $\pm0.039$ ${}^{+0.052}_{-0.051}$

CDF

${{\mathit p}}{{\overline{\mathit p}}}$ at $1.8$ TeV

$1.56$ ${}^{+0.14}_{-0.13}$ $\pm0.10$

SLD

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.532$ $\pm0.041$ $\pm0.040$

DLPH

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.49$ ${}^{+0.17}_{-0.15}$ ${}^{+0.08}_{-0.06}$

ALEP

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.61$ ${}^{+0.14}_{-0.13}$ $\pm0.08$

DLPH

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.53$ $\pm0.12$ $\pm0.08$

OPAL

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

• • We do not use the following data for averages, fits, limits, etc. • •

$1.515$ $\pm0.005$ $\pm0.006$

CMS

${{\mathit p}}{{\mathit p}}$ at 8 TeV

$1.507$ $\pm0.010$ $\pm0.008$

CDF

${{\mathit p}}{{\overline{\mathit p}}}$ at 1.96 TeV

$1.501$ ${}^{+0.078}_{-0.074}$ $\pm0.050$

D0

Repl. by ABAZOV 2012U

$1.524$ $\pm0.030$ $\pm0.016$

CDF

Repl. by AALTONEN 2011

$1.473$ ${}^{+0.052}_{-0.050}$ $\pm0.023$

D0

Repl. by ABAZOV 2005W

$1.40$ ${}^{+0.11}_{-0.10}$ $\pm0.03$

D0

Repl. by ABAZOV 2007S

$1.530$ $\pm0.043$ $\pm0.023$

D0

Repl. by ABAZOV 2009E

$1.54$ $\pm0.05$ $\pm0.02$

CDF

Repl. by AALTONEN 2011

$1.531$ $\pm0.021$ $\pm0.031$

DLPH

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.554$ $\pm0.030$ $\pm0.019$

BELL

Repl. by ABE 2005B

$1.523$ $\pm0.057$ $\pm0.053$

OPAL

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.58$ $\pm0.09$ $\pm0.02$

CDF

Repl. by ACOSTA 2002C

$1.52$ $\pm0.06$ $\pm0.04$

L3

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.54$ $\pm0.08$ $\pm0.06$

CDF

Repl. by ABE 1998Q

$1.55$ $\pm0.06$ $\pm0.03$

ALEP

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.61$ $\pm0.07$ $\pm0.04$

ALEP

Repl. by BARATE 2000R

$1.25$ ${}^{+0.15}_{-0.13}$ $\pm0.05$

ALEP

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.63$ $\pm0.14$ $\pm0.13$

DLPH

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.62$ $\pm0.12$

DLPH

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.57$ $\pm0.18$ $\pm0.08$

CDF

Repl. by ABE 1998B

$1.17$ ${}^{+0.29}_{-0.23}$ $\pm0.16$

DLPH

Sup. by ABREU 1995Q

$1.55$ $\pm0.25$ $\pm0.18$

DLPH

Sup. by ADAM 1995

$1.51$ ${}^{+0.24}_{-0.23}$ ${}^{+0.12}_{-0.14}$

OPAL

Sup. by AKERS 1995T

$1.52$ ${}^{+0.20}_{-0.18}$ ${}^{+0.07}_{-0.13}$

ALEP

Sup. by BUSKULIC 1996J

$1.20$ ${}^{+0.52}_{-0.36}$ ${}^{+0.16}_{-0.14}$

MRK2

${\it{}E}^{\it{}ee}_{\rm{}cm}$= 29 GeV

$0.82$ ${}^{+0.57}_{-0.37}$ $\pm0.27$

HRS

${\it{}E}^{\it{}ee}_{\rm{}cm}$= 29 GeV

¹	Measured using ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit K}^{*0}}$ decays.

²	Measured using ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit D}^{(*)-}}{{\mathit \pi}^{+}}$ decays.

³	Measured using ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit K}_S^0}$ decays.

⁴	Measured using ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit D}^{-}}{{\mathit \mu}^{+}}{{\mathit \nu}}{{\mathit X}}$ decays.

⁵	Measured using ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit K}^{+}}{{\mathit \pi}^{-}}$ decays.

⁶	Measured with ${{\mathit B}_{{{d}}}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}}({{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$) ${{\mathit K}_S^0}$ (${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$) decays.

⁷	Measured mean life using ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit K}^{*0}}$ decays.

⁸

Measured using a simultaneous fit of the ${{\mathit B}^{0}}$ lifetime and ${{\overline{\mathit B}}^{0}}{{\mathit B}^{0}}$ oscillation frequency $\Delta {\mathit m}_{{{\mathit d}}}$ in the partially reconstructed ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit D}^{*-}}{{\mathit \ell}}{{\mathit \nu}}$ decays.

⁹	Measurement performed using a combined fit of $\mathit CP$-violation, mixing and lifetimes.

¹⁰	AUBERT 2003C uses a sample of approximately 14,000 exclusively reconstructed ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit D}^{*}{(2010)}^{-}}{{\mathit \ell}}{{\mathit \nu}}$ and simultaneously measures the lifetime and oscillation frequency.

¹¹	Measurement performed with decays ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit D}^{-}}{{\mathit \pi}^{+}}$ and ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit D}^{-}}{{\mathit \rho}^{+}}$ using a partial reconstruction technique.

¹²	Measured mean life using fully reconstructed decays.

¹³	Data analyzed using partially reconstructed ${{\overline{\mathit B}}^{0}}$ $\rightarrow$ ${{\mathit D}^{*+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}}$ decays.

¹⁴	Events are selected in which one ${{\mathit B}}$ meson is fully reconstructed while the second ${{\mathit B}}~$meson is reconstructed inclusively.

¹⁵	Data analyzed using ${{\mathit D}}$ / ${{\mathit D}^{*}}{{\mathit \ell}}$ X event vertices.

¹⁶	Data analyzed using charge of secondary vertex.

¹⁷	Reported the combined measurement of $1.64$ $\pm0.08$ $\pm0.08$ ps${}^{-1}$ using the charge of the secondary vertex with the lepton and without. Only the flavor-specific measurement with the lepton is reported and used.

¹⁸	Data analyzed using inclusive ${{\mathit D}}/{{\mathit D}^{*}}{{\mathit \ell}}{{\mathit X}}$.

¹⁹	Measured mean life using partially reconstructed ${{\mathit D}^{*-}}{{\mathit \pi}^{+}}$ X vertices.

²⁰	ABREU 1995Q assumes B(${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit D}^{**-}}{{\mathit \ell}^{+}}{{\mathit \nu}_{{{{{\mathit \ell}}}}}}$) = $3.2$ $\pm1.7\%$.

²¹	AKERS 1995T assumes B(${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit D}_{{{s}}}}{}^{()}$ ${{\mathit D}^{0}}{}^{()}$) = $5.0$ $\pm0.9\%$ to find ${{\mathit B}^{+}}/{{\mathit B}^{0}}$ yield.

²²	Measured using ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit K}^{*}{(892)}^{0}}$ and ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit K}_S^0}$ decays.

²³	Measured mean life using fully reconstructed decays (${{\mathit J / \psi}}{{\mathit K}^{(*)}}$).

²⁴	Measured using the time-dependent angular analysis of ${{\mathit B}_{{{d}}}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit K}^{*0}}$ decays.

²⁵	Measurement performed using an inclusive reconstruction and ${{\mathit B}}$ flavor identification technique.

²⁶	Combined result of ${{\mathit D}}/{{\mathit D}^{}}{{\mathit \ell}}$ x analysis, fully reconstructed ${{\mathit B}}$ analysis, and partially reconstructed ${{\mathit D}^{-}}{{\mathit \pi}^{+}}$ X analysis.

²⁷	Data analyzed using vertex-charge technique to tag ${{\mathit B}}$ charge.

²⁸	Combined ABREU 1995Q and ADAM 1995 result.

²⁹	WAGNER 1990 tagged ${{\mathit B}^{0}}$ mesons by their decays into ${{\mathit D}^{-}}{{\mathit e}^{+}}{{\mathit \nu}}$ and ${{\mathit D}^{-}}{{\mathit \mu}^{+}}{{\mathit \nu}}$ where the ${{\mathit D}^{*-}}$ is tagged by its decay into ${{\mathit \pi}^{-}}{{\overline{\mathit D}}^{0}}$.

³⁰	AVERILL 1989 is an estimate of the ${{\mathit B}^{0}}$ mean lifetime assuming that ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit D}^{*+}}$ + X always.

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